Valveless compressor



Nov. 23, 1943. A. LAsow 2,334,939

VALVELESS COMPRESSOR Filed Jan. 12, 1945 INVENTOR. 41.55/27 LARSONATTORNEY Patented Nov. 23, 1943 UNITED STATES PATENT OFFICE VALVELESSCOMPRESSOR Albert Larson, Oakland, Calif., assignor to Harry Larson,Oakland, Calif.

Application January 12, 1943, Serial No. 472,119

2 Claims. (01. 230-172) This invention relates to a valveless compressorof a simple and rugged design. In many operations a supply of fluidunder pressure is desired. Heretofore compressors of the usual type,that is including valves for control of inlet and outlet have beenemployed. These are relatively ex pensive. valveless compressors havealso been suggested in the prior art but, so far as I am aware, none hasbeen particularly successful. The valveless compressor of the presentinvention is particularly characterized in that it is simple toconstruct, of a rugged design and possesses a high operating efficiency.

It is a, general object of the present invention to provide an improvedbut a simple and eflicient valveless compressor.

The invention includes other objects and features of advantage, some ofwhich, together with the foregoing will appear hereinafter wherein thepresent preferred form of a valveless compressor of this invention isshown and described.

In the drawing accompanying and forming a part hereof, Figure 1 is aside elevation, partly in section, of a valveless compressor of thisinvention.

Figure 2 is a fragmentary side elevation showing the inlet to thecompressor.

In the drawing I have shown a housing generally indicated by the numeral6. Mounted in the housing in any suitable manner is a crankshaft I whichis driven by any suitable power source. An eccentric 8 mounted upon thecrankshaft serves to reciprocate piston rod 9 connected to the eccentricby the follower ID. The piston rod carries the piston I2 thereon, thetwo being connected by pin I6 in the usual manner. The piston isreciprooated in cylinder structure I5 which is mounted upon the upperportion of the housing 6. Several piston rings I6 are preferably carriedby the piston. The provision of the cylinder and piston andreciprocation of the piston in the cylinder generally form no part ofthis invention and any suitable construction can be employed.

In accordance with this invention, fluid inlets I I are provided in theside wall I8 of the cylinder I5. The inlets are so positioned that thepiston is adjacent the bottom portion of its travel before the inletsare exposed. In this way, maximum permissible fluid admission can besecured before the piston closes off the inlet and begins itscompression stroke. As the piston moves upwardly it seals off the inletsI1 and compresses the fluid confined by the cylinder and by the pistonhead.

To permit of release of the fluid I form a passage I9 in the cylindersidewall, preferably oppo site to the inlet I! so that fluid trappedbetween the piston head and the cylinder head 2| can escape down thesidewall past the first piston ring I6 and enter inlet 22 to fluidpassage 23. This passage extends down along the piston to an outlet 2 3.As the piston reaches the upper portion of its travel the outlet 24overlaps aperture 26 in the cylinder wall I8 whereby fluid underpressure passes from between the cylinder and the piston head intoaperture 25 which is connected to a fluid receiver or some meansutilizing the compressed fluid.

In some cases it is desirable that fluid under pressure confined in thepassage 23 be released, particularly in the case of air. To this end Iform a slot 27 in the side wall so air released can scavenge thecrankcase of the compressor.

In case it is desired to vary the quantity of fluid delivered by thecompressor or to vary the pressure of the fluid delivered, the sidewallI8 can be tapped out adjacent to the passage I9 to permit insertion of arelatively large screw 3|. When this is moved into and out of passage I9the volumetric efficiency of the compressor can be varied considerablywhereby the pressure of the fluid delivered can be controlled. The body3| can also be formed with a needle valve 32 thereon permitting fluid tobe exhausted directly from the passage I9 through outlet port 34. Thisenables fluid to be bled off to vary the quantity delivered as well asthe pressure of the delivered I claim:

1. A compressor comprising a cylinder having a cylinder head and acylinder wall, a piston having a circular top and a side wall andmovable in said cylinder toward and away from said cylinder head, aninlet in said cylinder wall for admitting fluid to said cylinder whensaid inlet is uncovered by said piston, said inlet being provided insaid cylinder wall at a point whereat said inlet is exposed while saidpiston is substantially at the extreme of its travel away from saidhead, and an outlet from said cylinder comprising a first passage insaid cylinder side wall extending downwardly from said head, a secondpassage beginning below the top of the piston and extending along theside Wall of the piston, and an outlet through said cylinder wall, saidpassages serving to release fluid to said outlet which has beencompressed between the piston-head and cylinder.

2. A compressor as in claim 1 including a mem ber movable in said firstpassage to vary the volumetric efliciency of the compressor.

ALBERT LARSON.

